THE 2009 DECEMBER GAMMA-RAY FLARE OF 3C 454.3: THE MULTIFREQUENCY CAMPAIGN

Journal Article · Sun Jun 20 04:00:00 EDT 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/716/2/L170· OSTI ID:21451077

Pacciani, L; Vittorini, V; Tavani, M; Fiocchi, M T ^[1]; Vercellone, S; D'Ammando, F ^[2]; Sakamoto, T; Krimm, H A ^[3]; Pian, E ^[4]; Raiteri, C M; Villata, M ^[5]; Sasada, M; Itoh, R; Yamanaka, M ^[6]; Uemura, M ^[7]; Striani, E ^[8]; Fugazza, D ^[9]; Tiengo, A ^[10]; Stroh, M C

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1. INAF/IASF-Roma, I-00133 Roma (Italy)
2. INAF-IASF Palermo, Via Ugo La Malfa 153, I-90146 Palermo (Italy)
3. Center for Research and Exploration in Space Science and Technology (CRESST), NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
4. INAF-OATS, Via Tiepolo 11, I-34143 Trieste (Italy)
5. OATO-INAF, Strada Osservatorio 20, I-10025, Pino Torinese (Tonga) (Italy)
6. Department of Physical Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)
7. Hiroshima Astrophysical Science Center, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)
8. Dip. di Fisica, Univ. Tor Vergata, I-00133 Roma (Italy)
9. OAB-INAF, via Brera 28, I-20121 Milano (Italy)
10. INAF/IASF-Milano, I-20133 Milano (Italy)

During the month of 2009 December, the blazar 3C 454.3 became the brightest gamma-ray source in the sky, reaching a peak flux F {approx} 2000 x 10{sup -8} photons cm{sup -2} s{sup -1} for E > 100 MeV. Starting in 2009 November intensive multifrequency campaigns monitored the 3C 454 gamma-ray outburst. Here, we report on the results of a two-month campaign involving AGILE, INTEGRAL, Swift/XRT, Swift/BAT, and Rossi XTE for the high-energy observations and Swift/UVOT, KANATA, Goddard Robotic Telescope, and REM for the near-IR/optical/UV data. GASP/WEBT provided radio and additional optical data. We detected a long-term active emission phase lasting {approx}1 month at all wavelengths: in the gamma-ray band, peak emission was reached on 2009 December 2-3. Remarkably, this gamma-ray super-flare was not accompanied by correspondingly intense emission in the optical/UV band that reached a level substantially lower than the previous observations in 2007-2008. The lack of strong simultaneous optical brightening during the super-flare and the determination of the broadband spectral evolution severely constrain the theoretical modeling. We find that the pre- and post-flare broadband behavior can be explained by a one-zone model involving synchrotron self-Compton plus external Compton emission from an accretion disk and a broad-line region. However, the spectra of the 2009 December 2-3 super-flare and of the secondary peak emission on 2009 December 9 cannot be satisfactorily modeled by a simple one-zone model. An additional particle component is most likely active during these states.

• OSTI ID: 21451077
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 716; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
BOSONS
COSMIC GAMMA SOURCES
COSMIC RADIO SOURCES
COSMIC RAY SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
EMISSION
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
GAMMA RADIATION
IONIZING RADIATIONS
MASSLESS PARTICLES
PHOTON EMISSION
PHOTONS
QUASARS
RADIATIONS
TELESCOPES